Touch display

ABSTRACT

A touch display includes a first sealant, a surface adhesive and a second sealant disposed between a display panel and a touch panel. The first sealant is disposed on periphery of the touch display; the surface adhesive fills a space defined by the first sealant; and the second sealant is disposed outside of and surrounding the space defined by the first sealant.

CLAIM OF PRIORITY

The present application claims priority from Taiwan Application No.103105581, filed on Feb. 20, 2014 and entitled “TOUCH DISPLAY,” thecontents of which are expressly incorporated herein by reference intheir entirety.

1. Background of the Disclosure

The present invention generally relates to a touch display, and moreparticularly to a touch display with high bonding strength.

2. Description of Related Art

Touch screens, as input/output devices that adopt sensing technology anddisplay technology, have been widely employed in electronic devices suchas portable or hand-held electronic devices.

FIG. 1 shows a lateral view of a conventional touch display 100, whichmay primarily include a liquid crystal display panel 11 and a touchpanel 12. In order to obtain good visual perception, the liquid crystaldisplay panel 11 and the touch panel 12 are bonded together by anoptically-clear adhesive (OCA) 13.

During the process of manufacturing the touch display 100, however,faulty products may occur when there is defective bonding, therebyreducing yield. Faulty products from defective bonding typically need bereworked, resulting in material loss and waste. Moreover, the touchdisplay 100 according to the bonding architecture of FIG. 1 may have aweak bonding strength, which may reduce a product lifetime of the touchdisplay 100.

A need has thus arisen to propose a novel bonding structure, accordingto which disadvantages of the conventional touch display 100 may bereduced.

SUMMARY OF THE INVENTION

In view of the foregoing, it is an object of the embodiments of thepresent invention to provide a touch display which has an enhancedbonding strength and good light-transmittance, and has an improved yieldand product lifetime.

According to one embodiment, a touch display includes a display panel, atouch panel, a first sealant, a surface adhesive and a second sealant.The touch panel is disposed above the display panel. The first sealantis disposed between the display panel and the touch panel, and isdisposed on a periphery of the touch display. The surface adhesive isdisposed between the display panel and the touch panel, and fills aspace defined by the first sealant. The second sealant is disposedbetween the display panel and the touch panel, and surrounds the spacedefined by the first sealant.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a lateral view of a conventional touch display;

FIG. 2A shows a lateral view of a touch display according to a firstembodiment of the present invention;

FIG. 2B shows a top view of the touch display of FIG. 2A;

FIG. 3 shows a lateral view of a touch display according to a modifiedembodiment of the present invention;

FIG. 4 shows a top view of a touch display according to a secondembodiment of the present invention;

FIG. 5A shows a top view of a touch display according to a thirdembodiment of the present invention; and

FIG. 5B shows a top view of a touch display according to anothermodified embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 2A shows a lateral view of a touch display 200 according to a firstembodiment of the present invention, and FIG. 2B shows a top view of thetouch display 200 of FIG. 2A. In the specification, a direction “above”points to a touch position, and a direction “below” points against thetouch position.

In the embodiment, the touch display 200 includes a display panel 21(e.g., a liquid crystal display panel) and a touch panel 22. The touchpanel 22 is disposed above the display panel 21. A first sealant 23 isdisposed between the display panel 21 and the touch panel 22, and isdisposed on a periphery of, e.g. around or surrounding, an active area201 of the touch display 200. The first sealant 23 may have a frameshape, which may be closed as shown in FIG. 2B or open.

A surface adhesive 24 is disposed between the display panel 21 and thetouch panel 22, and fills a space defined by the first sealant 23. Inone embodiment, at least one post (not shown), sustained between thedisplay panel 21 and the touch panel 22, may be disposed within thespace defined by the first sealant 23.

According to one aspect of the embodiment, a second sealant 25 isdisposed outside of, e.g., around or surrounding, the space defined bythe first sealant 23. The second sealant 25 may have a frame shape,which may be closed as shown in FIG. 2B. A gap 26 may exist between thefirst sealant 23 and the second sealant 25. FIG. 3 shows a lateral viewof a touch display 300 according to a modified embodiment of the presentinvention. As distinct from FIG. 2A, there is no gap between the firstsealant 23 and the second sealant 25. The second sealant 25 may bereferred to as a reinforcement sealant, as it acts to reinforce thefirst sealant 23.

The first sealant 23, the surface adhesive 24 and the second sealant 25may be made of conventional optically-clear adhesive (OCA), which may beliquid or solid when being coated on or adhered with adherend. In anembodiment, one or more of the first sealant 23, the surface adhesive 24and the second sealant 25 may be made of a pressure-sensitive adhesive(PSA), which forms a bond with the display panel 21 and the touch panel22. For instance, bonding may occur when pressure is applied from thedisplay panel 21 and the touch panel 22. In another embodiment, one ormore of the first sealant 23, the surface adhesive 24 and the secondsealant 25 may be made of ultra-violet curing adhesive, which forms abond with the display panel 21 and the touch panel 22. For instance,bonding may occur when the ultra-violet curing adhesive is illuminatedwith ultra-violet light.

FIG. 4 shows a top view of a touch display 400 according to a secondembodiment of the present invention. In the embodiment, the secondsealant 25 has an open frame shape, which includes four L-shapeadhesives disposed around and external to four corners of a framedefined by the first sealant 23. There is no gap between the firstsealant 23 and the second sealant 25. In other embodiments, a gap mayexist between the first sealant 23 and the second sealant 25.

FIG. 5A shows a top view of a touch display 500 according to a thirdembodiment of the present invention. In the embodiment, the secondsealant 25 has an open frame shape, which includes two elongatedadhesives disposed around and external to two opposite sides (e.g., leftside and right side) of a frame defined by the first sealant 23. FIG. 5Bshows a top view of another touch display 501 according to anothermodified embodiment of the present invention. In the embodiment, thesecond sealant 25 includes two elongated adhesives disposed around andexternal to two opposite sides (e.g., top side and bottom side) of aframe defined by the first sealant 23. The embodiments of FIG. 5A andFIG. 5B do not exhibit a gap between the first sealant 23 and the secondsealant 25. In other embodiments, however, a gap may exist between thefirst sealant 23 and the second sealant 25.

In a further embodiment, the second sealant 25 may include four L-shapeadhesives of a type according to FIG. 4 in combination with a number(e.g., two or four) of elongated adhesives of a type according to FIG.5A and/or FIG. 5B.

In the embodiments discussed above, double sealants (i.e., the firstsealant 23 and the second sealant 25) are disposed between the displaypanel 21 and the touch panel 22. However, a greater number of sealantsmay be disposed between the display panel 21 and the touch panel 22 inother embodiments. As at least double sealants 23 and 25 are utilized inthe embodiments discussed above, bonding strengths greater than thoseassociated with conventional touch displays may be obtained whilemaintaining good light-transmittance. Moreover, the first sealant 23,the surface adhesive 24 and the second sealant 25 are discussed insequence to describe the touch display embodiments 200/300/400/500/501with an emphasis on structure rather than process or sequence.

Although specific embodiments have been illustrated and described, itwill be appreciated by those skilled in the art that variousmodifications may be made without departing from the scope of thepresent invention, which is intended to be limited solely by theappended claims.

What is claimed is:
 1. A touch display, comprising: a display panel; atouch panel disposed above the display panel; a first sealant disposedbetween the display panel and the touch panel, wherein an active area ispositioned between the display panel and the touch panel, and whereinthe first sealant is disposed on a periphery of the active area; asurface adhesive disposed between the display panel and the touch panel,wherein the surface adhesive is positioned in a space defined by thefirst sealant; and a second sealant disposed between the display paneland the touch panel, wherein the second sealant is disposed around thespace defined by the first sealant.
 2. The touch display of claim 1,wherein the first sealant has a closed frame shape.
 3. The touch displayof claim 1, wherein a gap exists between the first sealant and thesecond sealant.
 4. The touch display of claim 1, wherein no gap existsbetween the first sealant and the second sealant.
 5. The touch displayof claim 1, wherein one or more of the first sealant, the surfaceadhesive or the second sealant comprises pressure-sensitive adhesive. 6.The touch display of claim 1, wherein the second sealant has a closedframe shape.
 7. The touch display of claim 1, wherein the second sealantcomprises four L-shape adhesives disposed around four corners of a framedefined by the first sealant.
 8. The touch display of claim 1, whereinthe second sealant comprises two elongated adhesives disposed around twoopposite sides of a frame defined by the first sealant.